Hydraulic pressure-applying device



2 Sheets-Sheet 1 Filed March 6, 1944 N. .w WH,

l Y f larval-1to1- .:Hslzb er't y Oct. 9, 1945. H, E, PAGE 2,386,568

HYDRAULIC PRESSURE-APPLYING DEVICE f Filed March 6, 1944 2 Sheets-Sheet 2 Y. :HET' -r't EL Pac/15' 57,. .3 -EL/ m Patented Oct. 9, 1945 UNITED STATES PATENToFFlcF.

HYDRAULIC PRESSURE-APPLYING DEVICE Herbert E. Page, Pasadena, Calif. D Application March 6, 1944, Serial No. 525,259

(Cl. D-71) 3 Claims.

My invention relates to hydraulicl pressure generating and applying devices. One of the aims of my invention is to provide a device which utilizes a plurality of work chambers and pistons of progressively increasing diameters andin which device there is an automatic selection and utilization ofthe piston to meet the pressure requirements of a given operation.

Another object is to provide a hydraulic device l in which the work pistons project from opposite engaging member into initial contact with the work. y

A still further object .is toprovide a device in which the work pistons may be held stationary and the body be made movable relative thereto.

-From the following description of a presently preferred Aadaptation of the invention, it will be apparent that still further advantages are inherent in the invention and that it is susceptible of being carried-out in physical structures varying from the' specific form, arrangement and combination herein shown and described.

In the drawings, which will be referred to in conjunction with the following description:

Fig. l is a medial section;

Fig. 2 is an end view; and

' Fig. 3 is a fragmentary enlarged section showing details .of certain valve elements.

In the drawings, I show a body I presenting parallel cylinders 3, 4 and 5, valve-containing sockets 8, 1,' 3j and 9, valve chambers III, II, passageways, I4, I5, I3, I1, I8, I9, 20, 2|, 25, 26, 21, 23, 3| and 32, and a hydraulic fluid reservoir 30. The reservoir is at all times in communication with the inner ends 5a, 1d, 8a, 9a of the respective valve-,containing sockets 5, 1, 8 and 9,and is also at all times in communication with the valve elements through passageways 25, 29, 21 and 23, respectively. l'

A pumping piston 35 is reciprocally mounted in cylinder 3 and has rods 35a, 35h projecting from opposite sides or the ends of the body through threaded plugs 3l. Piston 35 divides cylinder 3 intochambers 3a, 3b. A iirst work piston 40 is reciprocally mounted in cylinder 4 and has rods 43a, 43h projecting from opposite ends of thebody through' plugs 4I. Piston 40 divides cylinder 4 into chambers 4a, 4b. A second work piston4 45 is reciprocally mounted in cylinder, 5 and has rods d 45a, 45b projecting through opposite ends of Athe body through plugs 48. APiston 45 divides cylinder 5 into chambers 5a, 5b.

- Work-contacting members 50, 5I are disposed at` the respective ends of the body I, and-are secured respectively to the opposite ends of the work piston rods 40a, 49h, 45a, 45h. Operating levers 52, 53, respectively, are pivotally mounted atop the 'respective members 50, 5 I The levers are pivotally connected to the respective outer ends of the pumping piston rods 35a, 35h by means of links 55.

Valves 60, 6I, 52 and 53 are mounted in the respective sockets 5, 1, 3 and 9. All said valves are of like construction and are more particularly described and claimed in my copending application Serial No. 508,444, filed October 30, i943, but will now be described, like reference numerals applying to the component elements of each of the said valves.

Each of the valves 90, 6I, 52, B3 comprises .a tubular body 10 held in its socket by snap ring 1I. A poppet housing 13 is held .in the inner end of the body 10 by a snap ring 14 and provides an inlet chamber 15 in communication with the reservoir through ports 16, 11, which latter port is controlled by poppet valve 11a seating towards the reservoir, being normally urged against its seat by a spring 13 and having oppositely disposed stems 19, 30. 'A I'he outerend of each stem 19 is concaved as shown by dotted line in Fig. 3.

A tubular plunger 83 is reciprocally mounted in the outer end of the valve body, there being provided between its inner endand theinner end wall of poppet housing 13 a pressure chamber 54, communicatingwith the inlet chamber 15 through a port 85 controlled by a ball valve 86 seating towards the inlet chamber. Pressure chamber 34 communicates with cylinder 4 through passageways I4, I5 and inlet chamber 15 communicates with cylinder 3 through passageway I9.

Plunger 83 has a longitudinal bore 83a in the left-hand or outer end of which a plug 88 is held by a snap ring 99, the plug having an opening 90. 'Ihe inner end of the plunger bore 33a has reciprocally mounted therein a secondary plunger 9| whose outer end is recessed'at 92 to receive ball valve 86. A coil springll is provided between the main plunger portion 83h and an annular iiange on the seconda.y plunger. Port 3| in plunger 83 provides communication between the plunger bore and passageway I4.

A plug 94 fits in the inner end of a hollow poppet 93, being held therein by a snap ring 9,6-,anfl having a port 91 therethrough. Poppet 93 isnormally urged against its seat closing port 31 by a coil spring 33. Poppet 93 is normally urged against its seat closing opening 30 by a coil spring and a discharge port |0| is provided through the outer end of poppet 33. A pull member |02 is provided on a plug |03 interposed between the snap ring 1| and the outer end of the body 10. Aspring |05 interposed between the plug |03 and the annular flange |06 of plunger 83 normally urges said plunger inwardly to maintain ball 36 seated.

Within valve chambers |0, the respective piston valves ||4, ||5 are reciprocally mounted for the purposes` hereinafter to be described.

Poppet 11a of the valve element 60 is actuated by an eccentric cam mounted on a shaft |2| journaled in the body and operated by an exterior handle |2|a. The corresponding poppet 11a of valve element 62 is actuated by a like cam |25 mounted on a shaft |26 journaled in the body and operated by an exterior handle |21. The corresponding poppet 11a of valve element 6| is actuated by like cam |30 mounted on a shaft |3| journaled in the body and operated by an exterior handle which is not shown in Fig. 2 since it appears directly behind handle |2|a in that view.

And the corresponding poppet 11a of valve element 63 is actuated by a like cam |35 mounted on a shaft |36 journaled in the body and operated by an exterior handle which is not visible w in Fig. 2 since it appears directly behind handle element |21.

Valve'||4 is manually operable by a shaft |40 connected to the valve by a connecting rod |4|, shaft |40 being journaled in the body and having a'n external operating handle |42. Valve ||5 is manually operable by a shaft |45 connected to the valve by connecting rod |46, shaft |45 being journaled in the body and having an external operating handle |41.

The purposes and coaction of the elements which I have described will become apparent from the description of operation now to follow:

Assuming that member 50 is fixed and that body is movable relative thereto, assuming valve |4 is to be moved to the right to the dotted line position ||4a, assuming that valve element 6| is rendered inoperative by rotating cam |30 to unseat the poppet 11a and ball 66 of said valve element, and assuming further that valve element 63 is rendered inoperative by rotating cam |35 to unseat poppet 11a and ball 86 of that valve element, reciprocation of piston 35 by means of lever 52 will, on each inward stroke, draw uid from the reservoir 30 into chamber A3a through passageway I8 by virtue of unseating poppet 11a of valve element 60. On each outward movement of piston 35-leftward movement in the drawings-this fluid will be trapped in chamber 3a and thus the body will be moved to the` left by further outward movement of piston 35, since the spring pressure on ball 86 of valve 60 is suflicient to prevent that ball from being unseated by the fluid pressure in chamber 3a until the body encounters a substantial resistance such as may be offered bythe work load. Such resistance or work load would be positioned between the left-hand end of the body and the member 50.

During this initial movement/of the body into contact with the work, make-up fluid is drawn..-4 into work chamber 4a from the reservoir through' passageway 20, the vacuum unseating poppet 11a of valve element 62; and make-up iluid will be drawn into chamber 5a through passageway 3|.

When the body encounters the work load, further reciprocation of piston 35 will" cause the fluid pressure to unseat ball 36 against its spring pressure on each leftward movement or pressure stroke of piston 35 and force iluid past ball 03, through passageways |4, |5 into chamber 4a to cause the body to exert the work moving or compressing pressure.

Inasmuch as the back pressure from chamber 4a will act against the relatively large area 33e of plunger 33, the pressure of spring |05 will be relieved against ball 36, the latter ball being urged towards its seat merely by the relatively weak spring 01. so that the relatively greater pressure of spring |05 does not have to be overcome on each pressure stroke of, piston 35.

When the pressure in chamber 4a reaches a predetermined point, the fluid pressure acting upon ball 06 of valve element 62 will unseat that valve and pass into the relatively larger work chamber 5b and thus the work action will be carried on at a still more favorable volume-pressure ratio. The action of the pressure in chamber` 5a against the plunger portion 83e of valve element 62 likewise compresses spring |05 of that valve until said pressure is relieved, so that the ball 86 of that valve is urged towards its seat merely by the relatively light action of spring 01.

From the foregoing it will be observed that the body is moved relatively rapidly into contact with the work load and then will .automatically select the correct work piston (40 or 45) to overcome the load.

After body has contacted the load, the pumping piston 35 may be made double-acting by moving valve ||5 to the right to the dotted line position ||5a which will connect chamber 3b through the ports I3, I6, |5 with work chamber 4a, thus making pressure chambers out of both chambers 3a and 3b.

During the foregoing described operation of the device, the member 50 has been considered as fixed and body v| has been considered as moving to the left. The body may be caused to move to the right by operating the cams |20, |25 to unseat the poppet 11a in valve elements 60, 62 to render those valve elements inoperative, and by rotating the cams |30, |35 to render valve elements 6|, 63 operative and by moving valves I4, I5 to the left. With the valves in said relative positions, reciprocation of piston 35 will cause body to move to the right in a succession as before described except that inthis case valve 6| is being used instead of valve 60.

My` device may be operable also by making body fixed and the members 50, 5| movable relative to the body, in which event, by the operation before described, member 50 would be moved towards and member 5| would moved away from the body during the above-described operation of the,.device .to move the body to the left towards member 50, and when operated to move the body to the right towards member 5|, the members 50, 5| would be moved to the right.

If it be desired to lock the device hydraulically, this may be accomplished by leaving all the valves 60, 6|, 62, 63, ||4, ||5 in the positions shown in the drawings.

Holes H are provided in the body and in members 50, 5| so that it may be possible to subject any work to a tension load as by securing and one side to body |,lif the body is moving to the right. Or a compression load and a tension load may be simultaneously applied to the respective work loads, if desired.

l claim:

l. In a. hydraulic pressure-generating device, the combination of a work-engaging body presenting a work cylinder, a pair of work-engaging members disposed respectively at opposite sides of the body, andl hydaulic, means for causing relative movement as between the body and the work-engaging members` whereby to act upon work positioned therebetween, said means including a work position reciprocally disposed in the work cylinder, a pair of connecting rods projecting from opposite sides of the body, said rods being connected at one end to the work piston and connected at their other ends to the respective work-engaging members, a pressure-generating cylinder presented by the body parallel to the work cylinder, a pumping piston reciprocally mounted in the pressure-generating cylinder and forming therewith opposed pressure chambers to which the respective opposite faces of the pump-A ing piston are exposed, ports providing communication' between the pressure .chambers and the work cylinder, valve means controlling said ports and being operable selectively to communicate.

pressure to the work cylinder at either side of the work piston therein, a check valve in each of said ports and a spring normally urging each of the check valves seated away from the work cylinder, each of said springs being yieldable cylinder, a pumping piston in the pressure generating cylinder, said piston having a rod extending outwardly through-one of the work-engaging sides of the body, an actuating lever pivotally secured to one of the work-engaging members.

and operatively connected to the outer end of the rod, a work piston in the work cylinder, connecting rod means secured to opposite sides of the work piston and extending outwardly through the work-engaging sides of the body, said rod means being connected to the respective workengaging members, a fluid reservoir, valve controlled means providing communication between the reservoir and pressure generating cylinder and valve-controlled means providing communication between the pressure generating and work cylinders.

.3. In a hydraulic pressure-generating device, the combination of a body vhaving oppositely disposed work-engaging sides, a transverse bore in the body providing a pressure generating cylinder, a pair of work-engaging members disposed in opposed relationship to the respectivev workengaging sides of the body, a pair of work cylinders of relatively different diameters transversely of the body parallel to each other and to the pressure generating cylinder, a pumping piston mounted in the pressure generating cylinder, actuating means for said pumping piston, a

work piston in each work cylinder, each work pist0n having opposite connecting rod means 'operatively connecting it to the respective 'work engaging` members, a` iiuid reservoir, valve controlled means providing communication between the reservoir and pressure generating cylinder, valve controlled means. providing selective communication between the pressure generating cylinder and the smallest work cylinder at opposite sides of the work piston therein, conduit means extending between the smallest work cylinder at opposite sides of the work piston therein respectively to the larger work cylinder at opposite sides of the work piston thereima check valve in each of said conduits seating towards the smallest cylinder and 'spring means 'opposing movement of said valves oil.' their respective seats.

HERBERT E. PAGE.

the body parallel with the pressure generating y 

